Single-reflex digital cameras with which an optical image of a subject is converted into an electrical image signal and can be outputted are rapidly growing in popularity. With a single-reflex digital camera such as this, the camera system is made up of a camera body and an interchangeable lens that is removably mounted on the camera body. With this camera system, the basic function of the camera body is to form images of subjects, and the interchangeable lens has the optical function of constituting part of the imaging optical system.
With this single-reflex digital camera, when the user looks at a subject through the viewfinder, the light that is incident on the interchangeable lens (that is, the subject image) is reflected by a reflecting mirror disposed along the optical path to the rear of the interchangeable lens, and is incident on a pentaprism. As a result, the subject image is converted by the pentaprism into an erect image, and the user can see the subject image through the optical viewfinder.
Also, with this single-reflex digital camera, since a plurality of interchangeable lenses of different focal length can be mounted on a single camera body, the user can photograph a wide variety of scenes using the interchangeable lens best suited to each scene.
Meanwhile, there has been a proposal for standards for a single-reflex camera system in which the communication system between the camera body and the interchangeable lens, the lens mount, and so forth are standardized in order to make such products more convenient to use. This would make these products interchangeable as long as the camera body and interchangeable lens met the standards, so a user could combine camera main bodies and interchangeable lenses made by different manufacturers.
Thus, these single-reflex digital cameras have become a system that is extremely convenient to use, which means that as these single-reflex digital cameras become more popular, they can be used not only by the professionals and experienced amateurs who used them in the past, but also by beginners and so forth.
Nevertheless, even with a single-reflex digital camera, just as with ordinary digital cameras, hand shake often adversely affects the resulting photographic image. Therefore, as the number of pixels increases in the imaging sensors built into the camera body, and as the enlarged printing of these photographic images becomes more prevalent, for example, the effect of hand shake becomes more pronounced. The effect of hand shake is even more pronounced when the camera is used by a novice.
In view of this, a camera system has been proposed for a single-reflex digital camera, in which an optical image blur corrector for adjusting the optical path and thereby correcting image blur caused by hand shake is built into an interchangeable lens (see Patent Document 1, for example).
Patent Document 1: Japanese Laid-Open Patent Application H10-73860